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// University of Rochester
// Department of Computer Science
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#ifndef __SERIALIZER_H__
#define __SERIALIZER_H__

#include "ContentionManager.hpp"
#include "../support/atomic_ops.h"

namespace stm
{
  /**
   *  Serializer uses time-based priority (in this case, increments of a
   *  global shared) in a blocking policy (always defer to older)
   */
  class Serializer : public ContentionManager
  {
    private:
      unsigned long timestamp; // For priority

      static volatile unsigned long timeCounter;

      ConflictResolutions shouldAbort(ContentionManager* enemy)
      {
          Serializer* B = static_cast<Serializer*>(enemy);
          if (timestamp < B->timestamp)
              return AbortOther;
          else
              return Wait;
      }

    public:
      Serializer() { }
      virtual void onBeginTransaction()
      {
          timestamp = fai(&timeCounter);
      }

      virtual ConflictResolutions onRAW(ContentionManager* e)
      {
          return shouldAbort(e);
      }
      virtual ConflictResolutions onWAR(ContentionManager* e)
      {
          return shouldAbort(e);
      }
      virtual ConflictResolutions onWAW(ContentionManager* e)
      {
          return shouldAbort(e);
      }

  };
}; // namespace stm

#endif // __SERIALIZER_H__
